This invention is directed toward rapidly dispersible absorbent products and methods for making and using such products. This invention is especially directed toward rapidly dispersible absorbent products that are urinal flushable.
In the anatomy of men and women, urine that collects in the bladder is excreted during the act of urination by passage through the urethra tube, ultimately exiting from the glans penis or the external urethral opening. For a high proportion of the population, a significant amount of residual urine temporarily remains in the urethral tube after urination. This occurrence is even more pronounced in males if the prostrate gland is enlarged, which restricts the flow of urine through the urethral tube. This effect, sometimes referred to as post-urinary drip, typically increases with age of the individual, and is especially common with males. Residual urine in the urethra tube eventually exits the urethra tube, though delayed subsequent to the primary excretion of urine. Residual urine also includes urine that temporarily adheres to the outer surface of the glans penis. Eventually residual urine will flow by gravity, agitation, and/or capillary action, and can soil the underclothing or trousers. In many cases, the residual urine drips during the period when the individual is dressing himself, such that the urine drips onto his clothing or onto the floor. The latter situation of dripping onto the floor is especially prevalent when the individual has urinated at an upright urinal, such as found in many public lavatories. In some cases a man may forcefully shake the penis in order to facilitate discharge of the residual urine. However in the course of shaking, the path of the urine is uncertain and the urine may contact the hands, clothing, wall and/or floor, or an adjacent person. Further, the shaking action is often only partially successful in discharging the residual urine. The situation presented by post-urination residual urine is generally unsanitary, and can lead to the spread of contagious disease. It can also cause malodor of the clothing or person, and in bathrooms, restrooms, and public lavatories, especially when usage is frequent.
Although various devices and absorbent products have been earlier disclosed to cope with this problem, such earlier expedients have been either too expensive, impractical, uncomfortable, or difficult to use. Whatever the reason for any particular device or product, the use of such devices or products has not achieved significant levels of usage in most societies. To the contrary, many people, simply allow residual urine to drip onto the floor, edge of the toilet or urinal, or their clothing. Some people use woven fabrics to wipe away residual urine and the fabric is then stored in the person""s pocket or carry bag and subsequently reused. This is disadvantageous in that it requires the person to store urine-soiled material with him throughout the day. Possibly the simplest approach has been to use conventional toilet paper to absorb the residual urine. This, however, has several disadvantages. Toilet paper is often not easily accessible at public urinals that are very commonly found in men""s public lavatories, but rather only located adjacent to toilets or in toilet stalls. Toilet paper also allows rapid strike-through of the urine through the thickness of the sheet, leading to wetting of the hand used to hold the paper. Finally, although toilet paper is generally flushable down a toilet, it quite often is not easily flushable down urinals, many of which have much smaller drain regions than toilets. In fact many urinals have a grid-like pattern of small orifices that make it particularly difficult to flush absorbent products down the drain. Attempts to flush toilet paper down such urinals leads to build-up of wet toilet paper in the urinal and clogging. Furthermore, toilet paper typically contains polymeric binders for providing wet strength to the sheet. These binders are important for providing the tensile strength needed for the sheets to perform well for their intended purpose. However they adversely affect the ability of the sheet to disperse into small segments or fibers that would be easily flushable down many urinal orifices and grids. Further, wet strength resins can adversely affect the toilet paper""s ability to generate hydrostatic or capillary pressure. Thus, conventional toilet paper sheets are not particularly useful for use as male urinary wipes.
A variety of other approaches have been suggested for absorbing body fluids. For example, U.S. Pat. No. 5,074,853 issued Dec. 24, 1991 to Bryant discloses a male incontinence diaper. U.S. Pat. No. 5.009,649 issued Apr. 23, 1991 to Goulter, et al. discloses an expandable banded male urinary incontinence condom and supporting undergarment. U.S. Pat. No. 4,790,835 issued Dec. 13, 1988 to Elias discloses a urinary male diaper. U.S. Pat. No. 4,673,401 issued Jun. 16, 1987 to Jensen et al. discloses a male incontinence device. U.S. Pat. No. 4,944,733 issued Jul. 31, 1990 to Casaie discloses a diaper for use in toilet training male children or for use by incontinent male adults. U.S. Pat. No. 4,675,012 issued Jun. 23, 1987 to Rooyakkers discloses a method for forming an absorbent genitalia pouch for incontinent males. U.S. Pat. No. 4,064,880 issued Dec. 27, 1977 to Logan discloses a sanitary napkin for male hygiene comprising a tubular absorbent web.
These devices and others of their type may be effective for absorbing relatively large volumes of urine. However they are not practical alternatives for most people, who would not typically be receptive toward wearing diapers, condoms, or their equivalents on a continuous basis. Further, they are not necessarily designed for absorbing urine to prevent post-urinary drip. They are intended to absorb excreted urine that escapes the urethra tube and remain in place until the user removes them, often at a much later time. Thus, such users do not experience the problems associated with residual urine since the absorbent device remains in place until well after any residual urine will have been discharged.
Additionally, numerous approaches have been tried to provide flushable fibrous products for use in a variety of uses including, but not necessarily limited to, sanitary napkins, diapers, toilet seat wipes, and the like. For example: U.S. Pat. No. 5,300,358 issued Apr 5, 1994 to Evers discloses a degradable and flushable absorbent structure for sanitary napkins, diapers, and the like having an absorbent fibrous core and a backsheet comprising a cold water soluble material; U.S. Pat. No. 4,575,891 issued Mar. 18, 1986 to M. Valente discloses a small flushable toilet seat wipe of approximately 2 inches by 2 inches having a cardboard upper layer; GB Pat. No. Publication 2,281,081, published Feb. 22, 1995 by R. L. Lewis et al. discloses a web of fibrous material and polymeric binder which is said to be sufficiently hydrodisintegratable to be flushed down a toilet. The binder is applied by spraying or dipping onto wet-laid or air-laid webs. EP patent Publication 896,089 A1 published Feb. 10, 1999 by Taakeuchi et al. discloses a fibrous sheet that is disintegratable when immersed in large amounts of water comprising a fibrous sheet treated with a binder such as polyvinyl alcohol. U.S. Pat. No. 4,734,941 issued Apr. 5, 1988 to De Witt et al. discloses a flushable urine-conducting product for positioning between the legs of a female to direct urine to a receptacle. The product comprises a fibrous or non-fibrous sheet that is disintegratable in water and a water soluble polymer film. The preferred disintegratable sheet is tissue paper. U.S. Pat. No. 5,509,913 issued Apr. 23, 1996 to Yeo discloses a toilet flushable products such as diapers, fabrics, and sheets for use as wipes that are insoluble in the presence of body waste fluid but soluble in the presence of normal tap water. These patents generally address the issue of flushability in toilets, but they do not disclose products specifically designed for absorbing residual urine or post-urinary drip. They also discuss flushability from the context of toilets, as opposed to urinals, as found in most public male lavatories.
More recently, U.S. Ser. No. 09/150,476, filed Sep. 9, 1998 discloses flushable hand held absorbent devices for absorption of post urinary drip that are flushable in both toilets and urinals. It remains desirable, however, to provide absorbent products that are flushable down all types of urinalsxe2x80x94including those with relatively large flush tubes as well as those having a plurality of relatively small orifices through which the urine must pass before being flushed out of the urinal receptacle. U.S. Ser. No. 09/235977, filed Jan. 22, 1999 discloses an absorbent device for absorbing residual urine with a transformable package.
What is needed is a convenient, easy-to-use, and easy to dispose of absorbent product that could be conveniently and discretely dispense one whenever needed, absorb residual urine, and then easily dispose of it in a convenient manner.
Therefore, it is an object of this invention to provide absorbent products useful for absorption of residual urine that are sufficiently dispersible and/or dissolvable such that they can be easily flushed through both urinals having relatively large orifices as well as urinals having relatively small orifices.
It is further an object of this invention to provide absorbent products as described above that are resistant to absorbed urine penetrating through the product and contacting the hand the user.
It is a further object of this invention to provide absorbent products as described above which can be discretely used and disposed of.
It is further an object of this invention to provide a method of making highly dispersible absorbent sheets, such as but not limited to those described above.
It is still further an object of this invention to provide a method for absorbing residual urine subsequent to urination that is both convenient and sanitary.
It is yet another object of this invention to provide devices for dispensing absorbent products suitable for absorbing residual urine which are convenient to obtain absorbent devices from prior to or subsequent to urination.
These and other objects of the invention as hereinafter described may become apparent to one of ordinary skill in the art are intended to be encompassed by the present invention in accordance with the claims which follow.
The present invention provides highly dispersible absorbent products, comprising an absorbent structure and preferably a water soluble barrier layer, wherein the absorbent products have a high rate of dispersibility, can exhibit low residual by-product in urinals upon flushing, resist strikethrough of absorbed fluid onto the hand of the user, and can absorb a sufficient amount of fluid without becoming overloaded and suffering from leakage. This invention further provides a method of making such dispersible absorbent products comprising mechanically weakening an absorbent structure. The present invention further comprises packaged products comprising a package and a plurality of dispersible absorbent products or articles. The present invention further provides a method for absorbing residual urine that can be both discreet and convenient, comprising absorbing residual urine subsequent to urination with a dispersible absorbent product of the present invention and depositing product in a toilet or preferably a urinal.